Apparatus for manufacture of spiral shells for concrete piles



@cih 24, E33 T. L. HUGHES ET AL APPARATUS FOR MANUFACTURE OF SPIRAL SHELLS FOR CONCRETE PILES 4 Sheets-Sheet l Filed Nov. 7, 1951 UNAH ` ATTORNEYS Q2/JWM YM TCRSZ 1 INVEN lmw Oct. 24, 1933. T HUGHES ET AL 1,932,271

APPARATUS FOR MANUFACTURE OF SPIRAL SHELLS FOR CONCRETE PILES Filed Nov. '7. 1931 4 Sheets-Sheet 2 F IGA INVENTORS ATTORNEY s' f ./M M

Oct. 24, 1933. T HUGHES ET AL 1,932,271

APPARATUS I-oR MANUFACTURE 0F SPIRAL SHBLLS FOR CONCRETE PILES Filed Nov. 7. 1951 4 Sheets-Sheet 3 Kn vf 124 y INVENTO S f. BY ATTORNEY` Oct. 24, 1933. 1', L. HUGHES n' AL 1,932,271 I APPARATUS FOR MANUFACTURE OF SPIRAL SHELLS FOR CONCRETE PILES INVENTORS BY ATTORNEYS Patented Qct. Z4, 1933 UNrro STATES PATENT. OFFICE APPARATUS FOR MANUFACTURE 0F SPIRAL SHELLS FOR CONCRETEPILES Application November 7, 1931. Serial No. 573,534

7 Claims.

This invention pertains to the manufacture 'of shells for concrete piles,- especially shells of the tapered spiral type in which the shell is formed with a vhelical groove in which is tightly wound a stilfening wire.

In the manufacture of such shells it is customary to first Wind the wirey on a collapsible slightly tapered mandrel, then to place an ungrooved shell on the mandrel outside the wire, then to apply a forming tool to groove the shell around the wire, and nally to collapse the mandrel and remove the shell, which then is spirally grooved with the reinforcing wire in the groove.

It has been found in practice that application -of the forming tool tends to stretch the thin metal 'of the shell, so that after the grooving operation is'completed the groove in the shell does not engage the reinforcing wire as tightly as desired. An object of the present invention is to disclose a snubbing device adapted to hold the shell against rotation `so that thev mandrel and reinforcing wire may be screwed tightly into the grooved shell before removing the shell from the mandrel.

Further and other objects .and advantages will be apparent from the specification and claims,

and from the accompanying drawings which illustrate what is now considered the preferred embodiment of the invention.

Fig. l is a front viewofthe machine just as y the forming tool is completing the grooving of a shell.

' the right 0f Fig. 1.

Fig. 4 is a detail view on line 4-4 of Fig. 3 showing counterweight and air cylinder.

Fig. 5 is an enlarged section on line 5-5 of Fig. l, showing the air control system.

Fig. 6 is a View on line 6-6 of Fig. 5.

Fig. '7 is a cross-section on line 7-'7 of Fig. 6.

Fig. 8 is a section through the air control valve.

Fig. 9 is a view of the air valve on line 9 9 of Fig. 8.

Referring to Figs. l and 3, the machine has a hollow base upon which is supported for rotation a 4chuck 22 having slides 24, each slide supporting a leaf 26 of the vertical mandrel 28 which is collapsible by movement of slides 24. The upper end of the mandrel is supportedV for rotation by la bearing 30 on shaft 32 passing through tail stock 34, and vertically movable therethrough under control of air cylinder 36. The tail stock is pivoted at 38 on frame 4() yso that it may be swung ing the Wire winding roller 56 and grooving roller to one side to permit placing a shell on, or removing a shell from, the mandrel. The free end 42 ofthe tail stock is secured to frame in bracket 44 when in operative position. .Frame 40 is supported by parallel cylindrical columns 46 resting on base 20.

Also resting on base 20 are two substantially vertical beams 48 having guide ways 50cm which are slidable carriages 52 and 54 supporta 58 respectively, Shafts 60 passing upwardly through beams 48 serve to move the carriages along their guides. Beams 48 are adjustable at their upper ends to positions parallelwith the tapered sides of the mandrel. Power is supplied 7g. to the machine by shaft 62 and distributed by f suitable gears within or above base 20 so as to drive the parts .of the machine in synchronism.

In operation, with the mandrel expanded, .one end of the reinforcing wire 64 (Fig. 2) is fastened by a clamp (not shown) at the upper end of the mandrel and is then tightly wound helically downwardly around the rotating mandrel by winding roller 5 6 on carriage 52 .actuated a shaft .60. When the lower end of the mandrel is reached, the lowerl end of the wire is also clamped to the mandrel, and the winding roller, by means of lever 66 is `moved to inoperative position. While roller 56 is moving downwardly, grooving roll 58 is being movedupwardly by its carriage 54, so that when the wire Winding operation is iinished, roller 56 is at the bottom of the mandrel and roller 58 at the top, retracted, however, by mechanism not shown, to inoperative position away from the mandrel.

After the wire is wound on the mandrel, .bearing 30 is raised, tail stock 34 is swung to one side, an ungrooved shell 68 is dropped onto the mandrel surrounding the wire, andtail stock 34 and bearing 30are replaced in their operative positions. Then grooving roller 58 is placed against the shell and drawn downwardly while mandrel and shell `are rotating, to .groove the shell around the wire, as is best shown at '70 in Fig. 2. The grooving roll is then retracted from contact with the shell and the shell would then be ready for removal fromk the mandrel were yit not for the fact that the grooving operation stretched the metal of the shell so that the shell may not grip the reinforcing wire as tightly as it should. The present invention, which will now be described, is designed to correct that condition.

Mounted on the lower ends of columns 46 is a vertically movable frame 72, made for convenience in two parts fastened together by studs 74. Rollers 76 serve as contact members between frame 72 and columns 46. Passing horizontally through the frame 72 is a lever 78, pivoted on vertical bolt 80 passing through slots 82' and 84 and lockedin voperative position vtherein by head 86 and nut 88. The pivot bolt 80 may be locked in various positions, (as for instance those marked 1, 2, 3, 4 and 5 in Fig. 5) to accommodate levers 78 of the different lengths necessary for shells of indicated by the full and dotted lines of Fig. 5.

Pivotally mounted at 89 on a bracket 90 at one corner of frame 72 is an air cylinder 92,

the plunger in which is connected by piston rod4 94 at 96 to one end of lever 78. The other endr of lever 78 is connected at 98 to one end of a snubber band 100 which passes around the man-U drel and shell thereon, to be anchored at its other end at 102 on frame 72. VThe snubber band is faced with suitable friction material 104.

The weight of frame 72 and its attached parts is counter balanced by a counter weight 106, connection `being made between weight and frame by a cable 108 passing over a sheave 110 and attached to frame 72 by a yoke 112. Weight 106 somewhat overbalances the parts at the other end of the cable, and consequently rests constantly on the adjustable fitting 114 on the upper end of piston rod 116 projecting upwardly from plunger 118 in vertical air cylinder 120 bolted to the side of base 20. A rod 122 passing vertically through weight 106 serves to guide `the movement ofthe weight.

An air control Valve 124 having an operating lever 126 is supported on one of the guide beams 48. The piping from the valve to the operating cylinders will be understood from the somewhat diagrammatic illustration in Fig. 5. Air enters the valve through pipe or hose 128 entering inlet 130,.and exhausts from opening 132. Pipe or hose 134 connects opening 136 of the valve to the inner end of cylinder 92, while hose or pipes 138 and140 connect opening 142 of the "valve and pipe 143 simultaneously to the outer end of cylinder 92 and to the lower end of cylinder 120. Pipes 134 and 143 serve to support kthe valve on beam 48 through the instrumentality of clamps 144. rIfhe rotary member of the valve, under control of lever 126 is disc 146, which in its various positions serves to distribute the air through the valve for the purposes of the present invention.

After the grooving operation above described is completed, rotation of the mandrel is stopped and valve lever 126 is moved to admit air to pipes 138 and 140 whereby the plunger in cylinder 92, operating on the end of lever 78 to which it is attached at 96, rotates lever 78 counter clockwise about its fulcrum 80, while air through pipe 140 enters the lower end of cylinder 120 to pushupwardly on counter weight 106. The movement of lever 78 tightens band 100 around shell 68. The mandrel is then rotated in proper direction to screw the helical wire V(whichis fast to the tapered mandrel), into the tapered shell until it is tight. During this screwing operationl the shell is snubbed, or prevented from turning, by brake band 100, and at the same time the shell, brake band, and frame 72 are all drawn downwardly, plunger 118 assisting in the downward movement by pushing upwardly on counter weight 106.

After the screwing down operation is finished, valve lever 126 is moved to exhaust air from pipes different diameters, which 'may Vvary as 138 and 140 and to admit air through pipe 134 to the inner end of cylinder 92, thus forcing the plunger in cylinder 92 and lever 78 to their normal positions as in Fig. 5, with the snubber band out of contact with the shell. The air being eX- hausted from below plunger 140 permits weight 106 to restore frame 72 and the snubber to their normal elevated positions as in Fig. 3.

The ends of wire 64 are then released from the mandrel, the mandrel is collapsed, and the spirally .grooved, wire-'reinforced shell is then lifted off the mandrel, tail stock 34 being, of

course, shifted as previously described, to permit its removal.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the Vfollowing claims.

1. Ina machine of the class described, a mandrel adapted to twithin a thin metal shell and means for rotating said mandrel and shell, in combination with a snubber band supported around said shell and operable at the will of the operator for gripping said shell whereby rotation of said shell is prevented while rotation of said mandrel continues.

2. In a machine of the class described, in combination, a mandrel having a helical screw thread thereon and adapted to have a shell screwed thereon, means for rotating said mandrel, a snubber band and a support on the machine for gripping said shell to prevent rotation thereof while said mandrel is rotating. whereby said shell and band will travel longitudinally of the mandrel.

3. The invention set forth in claim 2 in which said mandrel and shell are tapered, whereby rotation of said mandrel relatively to said shell may tighten said shell on said mandrel. Y

4. In a machine of the class described, in combination, a tapered mandrel having a wire wound helically on the surface of said mandrel, and adapted to receive a shell having a helical groove foo threaded onto said helically wound wire,r means x for rotating said mandrel and shell, a snubbing band and a support on the machine adapted for temporarily preventing rotation of said shell with said mandrel, whereby said wire may be screwed more tightly into said helical groove.

5. In a machine of theclass described, a mandrel adapted to t within a thin metal shell and means for rotating said mandrel and shell, in combination with a snubber band around the shell, fluid operated means for causing said band to engage or disengage the shell, and means for controlling said fluid operated means.

6. In a machine of the class described, in combination, a mandrel having a helical screw thread thereon and adapted to have a shell screwed thereon, means for rotating said mandrel, a snubber band around the shell, fluid operated means for causing said band to engage said shell to prevent rotation thereof while said mandrel is rotating, whereby said shell will travel longitudinally of said mandrel, means for permitting said band to travel longitudinally with said shell, and means for simultaneously controlling said fluid operating means and said permitting means.

7. In a machine of the class described, in combination, a vertical tapered mandrel having a helical screw thread thereon and adapted to have a thin metal threaded shell screwed thereon,

means for rotating said mandrel, a snubber band n A around the shell while said shell is on said mandrel, uid operated means for causing said band to grip said shell to prevent rotation thereof while said mandrel is rotating, whereby said shell will travel downwardly on said mandrel, means for supporting said band whereby said band can move downwardly with said shell, a counterbalance weight for said band supporting means, a 

